I know that GSX selects a tug based on the weight class of the aircraft and the payload. However, even after understanding this system and reading the other posts on the forum, I am still confused and can't get the results I would like. For example, I load a session with the 777-300er, which has an empty weight of more than ~350,000 lbs. According to the forum, when my aircraft weight is more than 250,000 pounds, and I am at a parking spot with a radius of more than 15m, I should get the larger yellow tug, or the nose lifting tug. So shouldn't I be getting this tug in default as the aircraft weight is more than 250,000 lbs? However, even with full fuel load and full payload (almost 700,000 pounds), I still get the small tug used for the 737 and 321. It seems that no matter what my payload is or what spot I am using, the tugs are selected at random. Even when calling GSX (after I have my payload and fuel set to max) I don't understand why I am still getting the small tug used for single aisle aircraft at random. Again, it is random, as sometimes I do get the larger yellow tug, or the semi-larger white tug used for the 757/767/330. I don't understand what I am not getting the larger yellow tug used for the A380, 747, and 777 when my load is so heavy.